AU2012396750B2

AU2012396750B2 - SAPO-34 zeolite having diglycolamine as templating agent and synthesis method for the zeolite

Info

Publication number: AU2012396750B2
Application number: AU2012396750A
Authority: AU
Inventors: Dong FAN; Zhongmin Liu; Xiong SU; Peng Tian; Dehua Wang; Ying Zhang
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2012-12-10
Filing date: 2012-12-10
Publication date: 2015-08-27
Anticipated expiration: 2032-12-10
Also published as: KR101920959B1; WO2014089740A1; US20150315031A1; ZA201504518B; EA201591081A1; BR112015013359A2; EA025394B1; EP2930148B1; JP2016505492A; SG11201504127XA; KR20150082596A; EP2930148A4; US9611150B2; DK2930148T3; JP6076496B2; EP2930148A1; BR112015013359B1; AU2012396750A1

Abstract

Provided in the present invention is silicoaluminophosphate zeolite SAPO-34. Same is characterized in that the anhydrous chemical composition thereof is: mDGA·(S Si

Description

SAPO-34 molecular sieve using diglycolamine as template agent and method for preparing the same Technical Field 5 The present invention belongs to the field of SAPO molecular sieve, and specifically concerns a SAPO-34 molecular sieve and method for preparing the same. Background The Union Carbide Corporation (UCC) researched and developed a series of novel 10 silicoaluminophosphate molecular sieves SAPO-n in 1984 (US4440871 and US4499327), which were prepared by using organic amines as a template agent and using hydrated alumina, phosphoric acid and silica sol as an aluminum source, a silicon source and a phosphorus source, respectively. Firstly, a complex of organic amine/silicoaluminophosphate with microporous structure was obtained by a hydrothermal crystallization method, and then the template agent (organic amine) was removed by 15 calcination to obtain the SAPO-n molecular sieves. Among this kind of molecular sieves, SAPO-34 with CHA-type framework has shown an excellent catalytic activity and selectivity in methanol to olefins (MTO) process, due to its proper pore structure, proper Brsnsted acid property, higher specific surface area, preferable adsorption performance, high thermal stability, high hydrothermal stability and the like. 20 SAPO-34 is a molecular sieve with chabazite-type (CHA) framework containing 8-member ring ellipsoidal cage and 3-dimensional channel, which is formed by stacking of double six-rings according to ABC sequence. SAPO-34 is microporous molecular sieve with a pore size of 0.38 x 0.38 nm. Space group of SAPO-34 is R3m belonging to trigonal crystal system (J. Phys. Chem., 1990, 94: 2730). 25 SAPO-34 is formed by Si, Al, P and 0 whose composition change at some range, generally in the order of n(Si)<n(P)<n(Al). SAPO-34 molecular sieve is generally produced by a hydrothermal synthesis process which uses water as the solvent and is conducted in a sealed autoclave. The silicon source may be chosen from silica sol, 30 active silica and orthosilicate esters. The aluminum source may be chosen from active alumina, pseudo boehmite and alkoxy aluminum. Preferable silicon source and aluminum source are silica sol and pseudo boehmite. Phosphorus source is generally 85% phosphoric acid. The template agent commonly used comprises tetraethyl ammonium hydroxide (TEAOH), morpholine (MOR), piperidine, isopropylamine (i-PrNH2), triethylamine (TEA), diethylamine (DEA), dipropylamine, and the like, or a mixture thereof. 35 The structural-directing agent partly affects the microstructure, elemental composition, morphology of synthesized molecular sieve, thus producing an impact on the catalytic performance of synthesized molecular sieve. In the present invention, diglycolamine firstly is used as structure-directing agent for the hydrothermal 40 synthesis of pure SAPO-34 molecular sieve. The synthetic SAPO-34 molecular sieve has shown an excellent catalytic performance in catalytic reaction and a good gas absorption separation performance. Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. 1 It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. Disclosure 5 A preferred object of the present invention is to provide a SAPO-34 molecular sieve, whose chemical composition in the anhydrous state is expressed as: mDGA-(SiAlyPz)O 2 ; wherein DGA is diglycolamine, distributing in the cages and pores of said molecular sieve; m is the molar number of diglycolamine per one mole of (SiAlyPz)O 2 , and m is from 0.03 to 0.25; x, y, z respectively represents the molar number of Si, Al, P, and x is from 0.01 to 0.30, and y is from 0.40 to 0.60, and z is from 0.25 to 0.49, and x + y + z 10 =1. Preferably, x is from 0.07 to 0.26, and y is from 0.42 to 0.52, and z is from 0.28 to 0.45, and x + y + z =1. The diffraction peaks are shown in Table 2, according to the X-ray diffraction analysis of said SAPO-34 molecular sieve. The X-ray diffraction analysis result of said SAPO-34 molecular sieve at least includes the diffraction peaks as the following table: No. 20 d(A) 1 9.4445 9.36452 2 15.942 5.55943 3 17.7583 4.99471 4 22.9708 3.87175 5 29.428 3.03525 15 Another preferred object of the present invention is to provide a method for preparing SAPO-34 molecular sieve. Another preferred object of the present invention is to provide a SAPO-34 molecular sieve prepared using the above method and catalysts prepared from the same for acid-catalyzed reaction or oxygenates 2 0 to olefins reaction. Another preferred object of the present invention is to provide a material used for adsorption separation of CH4/CO 2 . 25 According to a first aspect, the invention provides a SAPO-34 molecular sieve whose chemical composition in the anhydrous state is expressed as: mDGA-(Si AlyPz)O 2 ; wherein, DGA is diglycolamine; m is the molar number of diglycolamine per one mole of (Si AlyPz)O 2 , and m is 30 from 0.03 to 0.25; x, y, z respectively represents the molar number of Si, Al, P, and x is from 0.01 to 0.30, and y is from 0.40 to 0.60, and z is from 0.25 to 0.49, and x + y + z =1. The technical problem to be solved in the present invention is that the SAPO-34 molecular sieve is 35 prepared in high purity under hydrothermal or solvothermal conditions, using diglycolamine as the structure-directing agent and using the phosphorus source, the silicon source and the aluminum source employed in usual molecular sieve synthesis as raw materials. 2 The present invention is characterized in including the preparation steps as follows: (a) deionized water, a silicon source, an aluminum source, a phosphorus source and DGA are mixed according to a certain ratio, and an initial gel mixture with following molar ratio is obtained: SiO 2 /A1 2 0 3 is from 0.05 to 2.5; 5 P 2 0 5 /A1 2

O

3 is from 0.5 to 1.5;

H

2 0/A1 2 0 3 is from 5 to 200; DGA/A1 2

O

3 is from 2.5 to 30, DGA is diglycolamine; (b) the initial gel mixture obtained in said step (a) is transferred into an autoclave, then sealed and heated to crystallization temperature range from 150'C to 220C, crystallized for crystallization time range from 10 5h to 72h under the autogenous pressure; (c) after finishing the crystallization, the solid product is separated, washed to neutral using deionized water and dried to obtain said SAPO-34 molecular sieve. In said step (a), the silicon source is one or more selected from silica sol, active silica, orthosilicate 15 esters and metakaolin; the aluminum source is one or more selected from aluminum salts, activated alumina, aluminum alkoxide and metakaolin; the phosphorus source is one or more selected from phosphoric acid, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, organophosphorous compounds and phosphorus oxides. 2 0 In said step (b), the crystallization is carried out statically or dynamically. In the initial gel mixture obtained in said step (a), the molar ratio of SiO 2 /A1 2 0 3 is preferable from 0.15 to 2.0. 25 In the initial gel mixture obtained in said step (a), the molar ratio of P 2 0 5 /A1 2 0 3 is preferable from 0.8 to 1.5. In the initial gel mixture obtained in said step (a), the molar ratio of H 2 0/A1 2 0 3 is preferable from 10 to 150. 30 In the initial gel mixture obtained in said step (a), the molar ratio of DGA/A1 2

O

3 is preferable from 5.5 to 16. The present invention also refers to a catalyst for acid-catalyzed reaction, which is obtained by 35 calcining at least one of said SAPO-34 molecular sieves or at least one of the SAPO-34 molecular sieves prepared by said methods, at a temperature from 400 to 700 'C in air. The present invention also refers to a catalyst for oxygenates to olefins reaction, which is obtained by calcining at least one of said SAPO-34 molecular sieves or at least one of the SAPO-34 molecular 40 sieves prepared by said methods, at a temperature from 400 to 700 'C in air. The present invention also refers to a material used for adsorption separation of CH 4 /C0 2 , which is obtained by calcining at least one of said SAPO-34 molecular sieves or at least one of the SAPO-34 molecular sieves prepared by said methods, at a temperature from 400 to 700 'C in air. 3 The present invention can bring the advantages including: (1) obtaining a SAPO-34 molecular sieve using diglycolamine as the template agent. (2) the SAPO-34 molecular prepared by said method in present invention having excellent catalytic 5 performance in the reaction of converting methanol or dimethyl ether to light olefins. (3) the SAPO-34 molecular prepared by said method in present invention having excellent adsorption separation selectivity of CH4 and CO 2 . Brief Description of the Drawings 10 Figure 1 is a scanning electron microscope image of the sample prepared in Example 1 (SEM). Specific Embodiments of the invention 15 The elemental analysis was determined using Magix 2424 X-ray fluorescence spectrometer (XRF) produced by Philips. The X-ray powder diffraction analysis (XRD) was determined using X'Pert PRO X-ray diffractometer produced by PANalytical, with Cu Ka radiation (=0. 15418 nm), operated at 40KV and 100mA. 20 The SEM morphology analysis was determined using KYKY-AMRAY-1000B scanning electron microscope produced by Scientific Instruments Factory of Chinese Academy of Sciences. Carbon-13 nuclear magnetic resonance analysis ( 13 C MAS NMR) was determined using Infinity plus 25 400WB Solid-state nuclear magnetic resonance spectrometer produced by Varian, with a BBO MAS probe operating at a magnetic field strength of 9.4T. CHN elemental analysis was determined using German Vario EL Cube elemental analyzer. 30 The present invention will be described in details by Examples, but the present invention is not limited to these Examples. Examples 1 35 The amount of ingredients, the crystallization condition and the sample elemental composition are shown in Table 1. The synthesis process was as follows: 14g of pseudoboehmite (with A1 2 0 3 mass percent of 72.5%) and 79.2g of deionized water were mixed homogeneously, and then 5.96g of silica sol (with Si0 2 mass percent of 30.24%) was added and stirred to smooth, and then 23.06g of phosphoric acid (with H 3 P0 4 mass percent of 85%) was added by droplets. 31.5g 40 diglycolamine(abbreviated as DGA, with mass percent of 99%) were added into the mixture, stirring to smooth to obtain the initial gel mixture. The initial gel mixture was transferred into a stainless steel autoclave. The molar ratio of the compositions in the initial gel mixture was 3.ODGA:0.30SiO 2 : 1A1 2 0 3 : 1P 2 0 5 :50H 2 0. 4 The autoclave was put into a stove and temperature programmed heated to 200C, dynamically crystallized for 48h. After finishing the crystallization, the solid product was centrifugal separated, washed and dried at 100 0 C in air to obtain the raw powder sample. The raw powder sample was detected with XRD and XRD data were shown in Table 2, indicating that the raw powder sample 5 prepared had the structural characteristics as same as SAPO-34 molecular sieve. The CHN elemental analysis of the raw powder sample obtained in Example 1 was detected, and the chemical compositions of the raw powder sample were obtained by normalization of the CHN elemental analysis results and the inorganic elemental analysis results detected by XRF. 10 Table 1: The list of amount of ingredients and crystallization conditions of the molecular sieves* Ex Molar Aluminum Phosphorus Silicon H 2 0 Crystal Crystal Chemical am amount source and source and source and lization lization Composition ple of DGA molar amount molar molar Tempe Time of A1 2 0 3 amount of amount of rature thereof P 2 0 5 thereof SiO 2 thereof 1 0.3mol pseudoboehmite phosphoric silica sol 5.Omol 200"C 48h 0.19DGA 0.10 mol acid 0.03mol (Sio.13Alo.49Po38)02 0. 1Omol 2 0.59mol aluminium phosphoric silica sol 1.6mol 80'7 48h 0.12DGA isopropoxide acid 0.005mol (Sio.o 1 Alo.o 5 0 Po 4 9 )0 2 0.1 mol 0.10mol 3 0.25mol aluminium phosphoric silica sol 0.5mol 00 C 24h 0.ODGA isopropoxide acid 0. 15mol (Sio.3oAlo.

45 Po.

25 )0 2 0.1 mol 0.1Omol 4 0.38mol y-alumina phosphoric silica sol 8.3mol 200 C 24h 0.08DGA 0.1 mol acid 0.1Omol (Sio.

2 5 Alo.

41 Po.

34 )0 2 0. 1Omol 5 0.5mol aluminum phosphoric active silica 2.6mol 190'C 48h 0.25DGA sulfate acid 0.25mol (Sio.

28 Alo.4 6 Po 26 )0 2 0.1mol 0.05mol 6 0.3mol aluminium phosphoric ethyl 1.2mol 00 C 24h 0.22DGA chloride acid orthosilicate (Sio.

20 Alo.

35 Po 4 5 )0 2 0.1 mol 0.15mol 0.08mol 7 1.Omol pseudoboehmite phosphoric silica sol 5. imol 200 0 C 24h 0.21DGA 0.1 mol acid 0.04mol (Sio.1 0 Alo.49Po.41)02 0.09mol 8 0.8mol aluminium phosphoric silica sol 10mol 2000C 24h 0. 17DGA. isopropoxide acid 0.01mol (Sio.

0 6 Alo.

6 0 Po 34 )0 2 0.1 mol 0.15mol 9 0.26mol pseudoboehmite ammonium silica sol 6.6mol 220 C 5h 0. 16DGA. 0.1 mol dihydrogen 0.06mol (Sio.14Alo.47Po39)02 phosphate 0. 1Omol 10 1.5mol pseudoboehmite diammonium active silica 2.2mol 00 C 24h 0. 18DGA. 0.1 mol hydrogen 0.06mol (Sio Alo.

49

PO.

4 0 )0 2 phosphate 0. 1Omol 11 2.Omol aluminum diammonium silica sol 8.8mol 00 C 18h 0.15DGA sulfate hydrogen 0.07mol (Sio.1Alo.47Po.37)02 0. imol phosphate 0. 15mol 12 0.3mol pseudoboehmite diammonium silica sol 6.5mol 80"C 24h 0.12DGA 0.1 mol hydrogen 0.12mol (Sio.

2 5 Alo.4 0 Po.

35 )0 2 phosphate 0. 12mol 5 13 0.4mol pseudoboehmite phosphoric active silica 12mol 2100C 18h 0. 19DGA. 0.1 mol anhydride 0.03mol (Sio.15Alo.49Po.36)O2 0. 13mol 14 0.39mol pseudoboehmite phosphoric silica sol 4.5mol 19TC 12h 0.19DGA. 0.1 mol acid 0.03mol (Sio.15Alo.49Po.36)O2 0. 1Omol 15 0.39mol aluminium phosphoric tetramethyl 6.5mol 150OC 72h 0.22DGA. isopropoxide acid orthosilicate (Sio.1 5 Alo.4 6 Po.

39 )0 2 0.1 mol 0.1Omol 0.03mol 16 0.30mol pseudoboehmite trimethyl silica sol 6.5mol 210 C 15h 0.17DGA. 0.1 mol phosphine 0.03mol (Sio.13Alo.4sPo.37)O2 0. 1Omol 17 0.35mol pseudoboehmite triethyl silica sol 6.5mol 1700 60h 0.19DGA. 0.1 mol phosphine 0.03mol (Sio.13Alo.4sPo.39)O2 0. 1Omol 18 0.8mol pseudoboehmite phosphoric silica sol 3.Omol 200T 24h 0.20DGA. 0.1 mol acid 0.20mol (Sio.

2 6 Alo.44P.30)O 2 0. 1Omol 19 3.00mol pseudoboehmite phosphoric silica sol 20mol 2 24h 0.21DGA 0.1 mol acid 0.03mol (Sio.15Alo.5oPo.35)O2 0. 1Omol Table2: XRD result of the sample obtained in Example 1 No. 20 d(A) 10OxI/1 0 1 9.4445 9.36452 66.76 2 12.7935 6.91968 15.26 3 13.9312 6.35701 6.2 4 15.942 5.55943 43.18 5 17.7583 4.99471 21.85 6 18.9695 4.67843 2.26 7 20.5083 4.33075 100 8 20.9495 4.24053 4.27 9 21.9655 4.04662 16.19 10 22.2848 3.98936 8.18 11 24.9225 3.57281 70.93 12 25.7931 3.45415 22.85 13 27.5092 3.24245 6.1 14 28.1221 3.17316 4.82 15 29.428 3.03525 3.39 16 30.4672 2.93405 42.98 17 31.0098 2.88394 25.27 18 32.2329 2.77725 1.71 19 33.4612 2.67805 4.49 20 34.3373 2.61171 7.7 21 35.9729 2.49663 6.8 22 39.5319 2.27967 3.7 23 43.2766 2.0907 3.73 24 47.4623 1.91563 4.54 6 25 49.3238 1.84761 2.58 26 50.6098 1.80364 6.32 27 53.0197 1.7272 4.94 28 55.2438 1.66281 2.49 29 58.1695 1.58595 0.83 30 59.3794 1.5565 1.83 Examples 2 to 19 The amount of ingredients and the crystallization conditions were shown in Table 1, and the synthesis processes were the same as Example 1. 5 The samples were detected with XRD. XRD data of samples were similar to Table 2, which showed that each corresponding peak had the same peak position and the ±10% difference of peak intensity, indicating the samples prepared had the structural characteristics as same as SAPO-34 molecular sieve. The elemental analysis results of the samples were shown in Table 1. 10 The raw powder samples obtained in Examples 1 to 10 were detected with 13C MAS NMR analysis respectively, comparing the results with the '3C MAS NMR standard spectrum of diglycolamine, only the resonance peak of diglycolamine was observed. 15 Example 20 The sample obtained in Example 1 was calcined at 550'C for 4 hours in air, then pressed, crushed and sieved to 20-40 mesh. 5.Og of the sample was added into a batch reactor loaded 30mL of ethanol to carry out an ethanol dehydration reaction evaluation. The reaction was carried out at 150'C under stirring. The result showed that ethanol conversion reached 92% and the selectivity for ether in 20 products was 92%. Example 21 The sample obtained in Example 1 was calcined at 550'C for 4 hours in air, then pressed, crushed and sieved to 20-40 mesh. 1.Og of the sample was weighted and loaded into a fixed bed reactor to carry out 25 a methanol to olefins reaction evaluation. The sample was activated at 550'C for 1 hour in nitrogen gas and reduced to 450'C to perform a reaction. Methanol was carried by nitrogen gas with a flow rate of 40 ml/min and the Weight Hour Space Velocity of the methanol was 4.0 h-'. The reaction products were analyzed by an on-line gas chromatograph (Varian3800, FID detector, capillary column was PoraPLOT Q-HT). The result was shown in Table 3. 30 Table 3: The reaction result of methanol to olefins on the sample Life Selective (mass%) * Sample (min) CH 4

C

2

H

4

C

2

H

6

C

3

H

6

C

3 H C4* C 5 * C 2

H

4

+C

3 H 6 Example 1 126 1.38 43.14 0.55 37.60 1.03 12.17 4.13 80.74 7 Example 22 The sample obtained in Example 10 was calcined at 550'C for 4 hours in air. The adsorption isotherms of CO 2 and CH4 were detected using Micrometrics ASAP 2020. Before being detected, the sample was degassed at 350'C for 4 hour under vacuum conditions. The adsorption isotherms were detected at the 5 temperature of 25 0 C and the pressure of 101kpa. Table 4: The adsorption separation result of C0 2 /CH4 on the sample Sample Adsorption Capacity (mmol/g) CO2/CH 4

CO

2

CH

4 Example 10 3.82 0.20 19.1 10 8

Claims

1. A SAPO-34 molecular sieve whose chemical composition in the anhydrous state is expressed as: mDGA-(SiAlyPz)O 2 ; wherein, 5 DGA is diglycolamine; m is the molar number of diglycolamine per one mole of (SiAlyPz)O 2 , and m is from 0.03 to 0.25; x, y, z respectively represents the molar number of Si, Al, P, and x is from 0.01 to 0.30, and y is from 0.40 to 0.60, and z is from 0.25 to 0.49, and x + y + z =1. 10

2. A SAPO-34 molecular sieve according to claim 1, wherein the X-ray diffraction spectrogram of said SAPO-34 molecular sieve includes the diffraction peaks at following peak positions: No. 20 1 9.4445 2 15.942 3 17.7583 4 22.9708 5 29.428

3. A method for preparing said SAPO-34 molecular sieve according to claim 1, including the steps as follows: 15 (a) deionized water, a silicon source, an aluminum source, a phosphorus source and DGA are mixed according to a certain ratio, and an initial gel mixture with following molar ratio is obtained: SiO 2 /A1 2 0 3 is from 0.05 to 2.5; P 2 0 5 /A1 2 O 3 is from 0.5 to 1.5; H 2 0/A1 2 0 3 is from 5 to 200; 20 DGA/A1 2 O 3 is from 2.5 to 30, DGA is diglycolamine; (b) the initial gel mixture obtained in said step (a) is transferred into an autoclave, then sealed and heated to crystallization temperature range from 150C to 220C, crystallized for crystallization time range from 5h to 72h under the autogenous pressure; (c) after finishing the crystallization, the solid product is separated, washed to neutral using deionized 25 water and dried to obtain said SAPO-34 molecular sieve.

4. A method according to claim 3, wherein in the initial gel mixture obtained in said step (a), the silicon source is one or more selected from silica sol, active silica, orthosilicate esters and metakaolin; the aluminum source is one or more selected from aluminum salts, activated alumina, aluminum 30 alkoxide and metakaolin; the phosphorus source is one or more selected from phosphoric acid, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, organophosphorous compounds and phosphorus oxides.

5. A method according to claim 3, wherein in said step (b), the crystallization is carried out statically 35 or dynamically.

6. A method according to claim 3, wherein in the initial gel mixture obtained in said step (a), the molar ratio of organic amine DGA to A1 2 0 3 SDA/A1 2 O 3 is from 5.5 to 16. 9

7. A catalyst for acid-catalyzed reaction, which is obtained by calcining at least one of said SAPO-34 molecular sieves according to claims or claim 2 or at least one of the SAPO-34 molecular sieves prepared by said methods according to any one of claims 3 to 6, at a temperature from 400 to 700 'C in 5 air.

8. A catalyst for oxygenates to olefins reaction, which is obtained by calcining at least one of said SAPO-34 molecular sieves according to claims or claim 2 or at least one of the SAPO-34 molecular sieves prepared by said methods according to to any one of claims 3 to 6, at a temperature from 400 to 10 700 C in air.

9. A material used for adsorption separation of CH 4 /C0 2 , which is obtained by calcining at least one of said SAPO-34 molecular sieves according to claims or claim 2 or at least one of the SAPO-34 molecular sieves prepared by said methods according to to any one of claims 3 to 6, at a temperature 15 from 400 to 700 C in air 10